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Generic method multiple (OR) type constraint
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You can access the value through Primary and Alternate
There are implicit converters between TP/TA and Either to allow you to pass either the values or an Either anywhere where one is expected. If you do pass an Either where a TA or TP is expected, but the Either contains the wrong type of value yo...
What's the fastest way to merge/join data.frames in R?
...he plyr timings here. Also note that the data.table do include the time to convert to data.table and set the key, for fareness.
This answer has been updated since originally answered in Dec 2010. The previous benchmark results are below. Please see revision history of this answer to see what chan...
Build fat static library (device + simulator) using Xcode and SDK 4+
...ary takes much more effort to setup, but much nicer long-term solution (it converts your library into a Framework).
Use this, then tweak it to add support for Archive builds - c.f. @Frederik's comment below on the changes he's using to make this work nicely with Archive mode.
RECENT CHANGES:
1. ...
The 3 different equals
What is the difference between = , == , and === ?
5 Answers
5
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Returning anonymous type in C#
I have a query that returns an anonymous type and the query is in a method. How do you write this:
15 Answers
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Most lightweight way to create a random string and a random hexadecimal number
What is the most lightweight way to create a random string of 30 characters like the following?
13 Answers
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Switching to a TabBar tab view programmatically?
Let's say I have a UIButton in one tab view in my iPhone app, and I want to have it open a different tab in the tab bar of the TabBarController . How would I write the code to do this?
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What is “entropy and information gain”?
...-1)/2) = prob_array(diff+(array_size-1)/2) + 1
endif
endfor
//Convert values in prob_array to probabilities and compute entropy
n = total(prob_array)
entrop = 0
for i = 0, array_size-1 do begin
prob_array(i) = prob_array(i)/n
//Base 2 log of x is Ln(x)/Ln(2). Take Ln of array ...
How to save picture to iPhone photo library?
... void *contextInfo);
You only need completionTarget, completionSelector and contextInfo if you want to be notified when the UIImage is done saving, otherwise you can pass in nil.
See the official documentation for UIImageWriteToSavedPhotosAlbum().
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How to programmatically clear application data
I am developing automated tests for an android application (using Robotium). In order to ensure the consistency and reliability of tests, I would like to start each test with clean state (of the application under test). In order to do so, I need to clear the app data. This can be done manually in Se...